The Story of the Soil; from the Basis of Absolute Science and Real Life

by Cyril G. Hopkins

CHAPTER XXIX

THE ULTIMATE COMPARISON

WILKES was at the side gate to meet Adelaide and Percy, and the grandmother stood at the door as they reached the veranda.

"Lucky for us you got back before the Thanksgiving scraps are all gone," she said to Percy, "but I suppose even our Thanksgiving fare will be poor picking after you've been living in Washington and Boston."

"Even the Thanksgiving dinner on the boat was not equal to this," said Percy, as they sat down to the table loaded with such an abundance of good things as is rarely seen except on the farmer's table. The "scraps," if such there were, had no appearance of being left-overs, and there was monster turkey, browned to perfection and sizzling hot, placed before Mr. West ready for the carving knife.

Percy had opened the letter from the chemist, but said to Mr. West that it would take him an hour or more to compute the results to the form of the actual elements and reduce them to pounds per acre in order to make possible a direct comparison between the requirements of crops, on the one hand, and the invoice of the soil and application of plant food in manure and fertilizers, on the other hand.

"Please let me help you make the computations," said Adelaide, much to the surprise of her parents, who knew that she took no interest in affairs pertaining to farming. "I like mathematics and will promise not to make any mistakes if you will tell me how to do some of the figuring."

"Thank you," said Percy. "With your help it will take only half the time that I should require alone."

This proved to be correct, for in half an hour after supper they had the results in simplified form. Even the mother and grandmother joined the circle as Percy began to discuss the results with Mr. West

"Now here is the invoice," said Percy, "of the surface soil from an acre of land where we collected the first composite sample,—the land which you said had not been cropped since you could remember. This soil contains plant food as follows:

1,440 pounds of nitrogen 380 pounds of phosphorus 15,760 pounds of potassium 3,340 pounds of magnesium 10,420 pounds of calcium

"I'd like to know how these amounts compare with what your Illinois soil contains," said Mr. West.

"We have several different kinds of soil in Illinois," replied Percy. "The common corn belt prairie soil is called brown silt loam. It contains, as an average, 5000 pounds of nitrogen and 1200 pounds of phosphorus, or nearly four times as much of each of those elements as this Virginia soil which you say is too poor to cultivate.

"I wrote to the Illinois Experiment Station before I left Washington to see if I could get the average composition of the heavier prairie soil, which occupies the very flat areas that were originally swampy, and one of the letters you had received for me gives 8000 pounds of nitrogen and 2000 pounds of phosphorus as the general average for that soil. That is our most productive land, and it contains about five times as much of these two very important elements as your poorest land.

"Our more common Illinois prairie contains about 35,000 pounds of potassium, 9,000 pounds of magnesium, and I 1,000 pounds of calcium. This is more than twice as much potassium and nearly three times as much magnesium as in your poorest land, but the calcium content is about the same in your soil as in ours. However, as you will remember, your soil is distinctly acid and consequently markedly in need of lime, the magnesium and calcium evidently being contained in part in the form of acid silicates with no carbonates; whereas, our brown silt loam is a neutral soil and our black clay loam contains much calcium carbonate, the same compound as pure limestone."

"I am anxious to know about our best land," said Mr. West. "What did the chemist find in the soil from the slope where we get the best corn after breaking up the old pastures?"

"He found the following amounts in the surface soil," said Percy.

800 pounds of nitrogen

1,660 pounds of phosphorus

34, 100 pounds of potassium

8,500 pounds of magnesium

13,100 pounds of calcium

"Rich in everything but nitrogen," Percy continued, "richer than our common prairies in phosphorus and calcium, and nearly as rich in potassium and magnesium; but very, very poor in nitrogen. Legume plants ought to grow well on that land, because the minerals are present in abundance, and, while lack of nitrogen in the soil will limit the yield of all grains and grasses, there is no nitrogen limit for the legume plants if infected with the proper nitrogen-fixing bacteria, provided, of course, that the soil is not acid. You will remember, however, that even this sloping land is more or less acid, although here and there we found pieces of undecomposed limestone. With a liberal use of ground limestone, any legumes suited to this soil and climate ought to grow luxuriantly on those slopes."

"That reminds me that we are greatly troubled with Japan clover on those slopes," said Mr. West. "Of course it makes good pasture for a few months, but it doesn't come so early in the spring as blue grass and it is killed with the first heavy frost in the fall. We like blue grass much better for that reason, but when we seed down for meadow and pasture, the Japan clover always crowds out the timothy and blue grass on those slopes."

"And when you plow under the Japan clover, you get one or two good crops of grain," said Percy, "because this clover has stored up some much needed nitrogen and the soil is rich in all other necessary elements. Have you ever tried alfalfa on that kind of land? That is a crop that ought to do well there, especially if limestone were applied."

"Yes, I have tried alfalfa," replied Mr. West, "and I tried it on a strip that ran across one of those steep slopes; but it failed completely, and, as I remember it, it was poorer on that hillside than on the more level land."

"Did you inoculate it?" Percy asked.

"Inoculate it? No. I didn't do anything to it, but just sow it the same as I sow red clover."

"What does it mean to inoculate it?" asked Adelaide.

"It means to put some bugs on it," said the grandmother; "some germs or microbes, or whatever they are called. Don't you remember, Adelaide, that I told you about that when I read it in the magazine a while ago? Don't you remember that somebody was making it and a man could carry enough in his vest pocket to fertilize an acre and he wanted $2 a package. Charles said that $1.50 a hundred was more than he could afford to pay for fertilizer, and he didn't care to pay $2 for a vest pocket package. Isn't that the stuff, Mr. Johnston?"

"It listens like it, as the Swedes say," said Percy, "but the advertisements of these germ cultures put out by commercial interests are usually very misleading. The safest and best and least expensive method of inoculating a field for alfalfa is to use infested soil taken from some old alfalfa field or from a patch of ground where the common sweet clover, or mellilotus, has been growing for several years. I saw the sweet clover growing along the railroad near Montplain, and there is one patch on the roadside right where—when you enter the valley on the way to the station."

"Right where Adelaide smashed that nigger's eye with her heel and helped Mr. Johnston capture them both," broke in the grandmother. "That's the only good thing I can say for her peg heeled shoes."

Adelaide colored and Percy now understood what had been a puzzle to him.

"The same bacteria," he went on quickly, "live upon both the sweet clover and the alfalfa, or at least they are interchangeable. These bacteria are not a fertilizer in any ordinary sense, but they are more in the nature of a disease, a kind of tuberculosis, as it were; except that they do much more good than harm. They attack the very tender young roots of the alfalfa and feed upon the nutritious sap, taking from it the phosphorus and other minerals and also the sugar or other carbohydrates needed for their own nourishment, since they have no power to secure carbon and oxygen from the air, as is done by all plants with green leaves. On the other hand, these bacteria have power to take the free nitrogen of the air, which enters the pores of the soil to some extent, and cause it to combine with food materials which are secured from the alfalfa sap, and thus the bacteria secure for themselves both nitrogen and the other essential plant foods. The alfalfa root or rootlet becomes enlarged at the point attacked by the bacteria, and a sort of wart or tubercle is formed which resembles a tiny potato, as large as clover seed on clover or alfalfa, and, singularly, about as large as peas on cowpeas or soy beans. On plants that are sparsely infected, these tubercles develop to a large size and often in clusters. While the bacteria themselves are extremely small and can be seen only by the aid of a powerful microscope, the tubercles in which they live are easily seen, and they are sufficient to enable us to know whether the plants are infected."

"I wish you would tell me the difference between the words inoculated and infected," said Adelaide.

"Inoculated is used in the active sense and infected in the passive," said Percy. "Thus the red clover growing in the field is infected if there are tubercles on its roots, although it may never have been inoculated; and we inoculate alfalfa because it would not be likely to become infected without direct inoculation."

"Under favorable conditions," continued Percy, "these bacteria multiply with tremendous rapidity, somewhat as the germs of small pox or yellow fever multiply if allowed to do so. A single tubercle may contain a million germs which if distributed uniformly over an acre would furnish more than twenty bacteria for every square foot."

"There, Charles," said the grandmother, "wouldn't a vest pocketful of those bugs or germs be a big enough dose for one acre?"

"Well, but they're not a fertilizer, Mother," said Mr. West, "and besides Mr. Johnston says it is better to use the infected sweet clover soil and there is no need of paying $2 an acre for something we knew nothing about, and especially on land that is not worth more than $2 an acre."

"I don't care what it's worth," she replied, "some of it cost your grandfather $68 an acre, and it will never be sold for any $2, while I have any say so about it."

They waited for Percy to proceed.

"The individual bacteria are very short-lived," he continued, "and products of decay soon begin to accumulate in the tubercles. These products contain, in combined form, nitrogen which the bacteria have taken from the air, and in this form it is taken from the tubercles and absorbed through the roots into the host plant and thus serves as a source of nitrogen for all of the agricultural legumes.

"It should be kept in mind, of course, that the red clover has one kind of nitrogen-fixing bacteria, that the cowpea has a different kind, and that the soy bean bacteria are still different, while a fourth kind lives on the roots of alfalfa and sweet clover."

"How much infected sweet clover soil would I need to inoculate an acre of land for alfalfa?" asked Mr. West.

"If the soil is thoroughly infected, a hundred pounds to the acre will do very well if applied at the same time the alfalfa seed is sown and immediately harrowed in with the seed. If allowed to lie for several hours or days exposed to the sunshine after being spread over the land the bacteria will be destroyed, for like most bacteria, such as those which lurk in milk pails to sour the milk, they are killed by the sunshine."

" That's right," said the grandmother. "That's the way to sterilize milk pails and pans and crocks. I like crocks better than pans. They don't have any sort of joints to dig out."

"Of course," continued Percy, "a wagon load of infected soil will make a more perfect inoculation than a hundred pounds, and where it costs nothing but the hauling it is well to use a liberal amount."

"How deep should it be taken?" asked Mr. West.

"About the same depth as you would plow. The tubercles are mostly within six or eight inches of the surface. The bacteria depend upon the nitrogen of the air and this must enter the surface soil. Sometimes in wet weather the tubercles can be found almost at the surface of the ground, and when the ground cracks one can often find tubercles sticking out in the cracks an inch or two beneath the surface but protected from direct sunshine.

"These bacteria have power to furnish very large amounts of nitrogen to such a crop as alfalfa. The Illinois Station reports having grown eight and one-half tons of alfalfa per acre in one season. It was harvested in four cuttings. The hay itself was worth at least $6 a ton above all expenses, which would bring $51 an acre net profit for one year. Of course this was above the average, which is only about four and one-half tons over a series of several years. But suppose you can save only three tons and get $6 a ton net for it, as you could easily do by feeding it to your cattle and sheep. That would bring $18 an acre or six per cent. interest on $300 land. I am altogether confident that this could be done on your sloping hillsides, with their rich supplies of phosphorus and other mineral foods, provided, of course, that you use plenty of ground limestone and thoroughly inoculate the soil."

"Well, I shall certainly try alfalfa again," said Mr. West, "and if I can grow such crops of alfalfa as you think on the hillsides, I can have much more farm manure produced for the improvement of the rest of the land. By the way what did that chemist find in that sample you took of the other land where it does not wash so much as on the steeper slopes."

"He found the following:

1,030 pounds of nitrogen 1,270 pounds of phosphorus 16,500 pounds of potassium 7,460 pounds of magnesium 16,100 pounds of calcium

"Well, the phosphorus is not so low," said Mr. West.

"Fully equal to that in our $150 Illinois prairie," replied Percy, "and again the calcium is more than ours, with magnesium not far below, and potassium half our supply. Nitrogen is plainly the most serious problem on most of this farm, and limestone and legumes must solve that problem if properly used."

"Do you think this land could be made as valuable as the Illinois land just by a liberal use of limestone and legumes?" asked Adelaide.

"I should have some doubt about that," Percy replied. "Your very level uplands that neither lose nor receive material from surface washing are very deficient in phosphorus and much poorer than ours in potassium and magnesium; and your undulating and steeply sloping lands are more or less broken, with many rock outcrops on the points and some impassable gullies, which as a rule compel the cultivation of the land in small irregular fields. A three-cornered field of from two to fifteen acres can never have quite the same value per acre as the land where forty or eighty acres of corn can be grown in a body with no necessity of omitting a single hill. Then there is some unavoidable loss from surface washing, so that to maintain the supply of organic matter and nitrogen will require a larger use of legumes than on level land of equal richness. In addition to this is the initial difference in humus content. This is well measured by the nitrogen content. While your soil contains eight hundred pounds of nitrogen on the steeper slopes and one thousand pounds on the more gently undulating areas, ours contains five thousand pounds in the brown silt loam and eight thousand pounds in the heavier black clay loam. This means that our Illinois prairie soil contains from five to ten times as much humus, or organic matter, as your best upland soil. To supply this difference in humus would require the addition of from four hundred to eight hundred tons per acre of average farm manure, or the plowing under of one hundred to two hundred tons of air-dry clover. This represents the great reserve of the Illinois prairie soils above the total supplies remaining in your soils.

"Our farmers are still producing crops very largely by drawing on this reserve. Of course most of this great supply of humus is very old. It represents the organic residues most resistant to decomposition; and, where corn and oats are grown exclusively, the soil has reached a condition on many farms under which the decomposition of the reserve organic matter is so slow that the nitrogen liberated from its own decay and the minerals liberated from the soil by the action of the decomposition products are not sufficient to meet the requirements of large crops, and for this reason alone some of our lands that are still rich are said to be run down; but they only require a moderate use of clover or farm manure or other fresh and active organic matter to at once restore their productiveness to a point almost equal to the yields from the virgin soil. Some Illinois farmers who have discovered this apparent restoration have jumped to the conclusion that they have solved the problem of permanently maintaining the fertility of the soil; and I judge from a remark made by the Secretary of Agriculture that some Iowa farmers have the same mistaken notions.

"These fresh supplies of active organic matter serve primarily as soil stimulants, hastening the liberation of nitrogen from the organic reserve and of minerals from the inorganic soil materials.

"Where one of the Eastern farmers has managed a farm under the rotation system with the occasional use of clover or light applications of farm manure,—where this has been continued until the great reserve is largely gone, and the phosphorus supply greatly depleted, then the land is truly run down, but not until then.

"Finally, land-plaster and quick-lime, still more powerful soil stimulants, are often brought into the system to bring about a more complete exhaustion of the soil reserves, and lastly the use of small amounts of high-priced commercial fertilizers serves to put the land in suitable condition for ultimate abandonment."

"Do you mean that commercial fertilizers injure the soil?" asked Mr.
West.

"Well, to some extent they injure the soil because they tend to destroy the limestone and increase the acidity of the soil, and also because they contain more or less manufactured land-plaster and thus serve as soil stimulants; but the chief point to keep in mind concerning the use of the common so-called complete commercial fertilizer is that they are too expensive to permit their use in sufficient quantities to positively enrich the soil. Thus the farmer may apply two hundred pounds of such a fertilizer at a cost of $3.00 an acre, and then harvest a crop of wheat, two crops of hay, pasture for another year or two, plow up the grounds for corn, apply another two hundred pounds for the corn crop, follow with a crop of oats, and then repeat. He thus harvests five crops and pastures a year or two and applies perhaps four hundred pounds of fertilizer at a cost of $6.00.

"As an average of the most common commercial fertilizers sold to the farmers in the Eastern and Southern States, the four hundred pounds would add to the soil seven pounds of nitrogen, fourteen pounds of phosphorus and seven pounds of potassium, while a single fifty-bushel crop of corn will remove from the soil ten times as much nitrogen, five times as much potassium, and nearly as much phosphorus as the total amounts applied in this six-year or seven-year rotation.

"In this manner the farmer extends the time during which he can take from the soil crops whose value exceed their cost. He applies only one-fourth or possibly one-half as much of the most deficient element as the crops harvested require, and thus he continues for a longer time to 'work the land for all that's in it! '"

"Well, isn't that the limit?" said Adelaide, with emphasis on the "isn't," for which she received a disapproving look from her mother, so far as her almost angel-face could give such a look.

"So far as human ingenuity has yet devised," replied Percy, "this system appears to be the limit; but this limit has not yet been reached on any Westover soil. If anyone can devise a method for extending this limit he should apply it on a type of soil covering more than two-fifths of the total area of St. Mary County and more than 45,000 acres of Prince George County, Maryland, some of which almost adjoins the District of Columbia. This soil has been reduced in fertility until it contains only one-third as much phosphorus as your poorest land. I found a Western man who had come down to Maryland a few years ago. He saw that beautiful almost level upland soil, and it looked so good to him that he bought and kept buying until he had 'squared out' a tract of eleven hundred acres. He still had left money enough to fence the farm and to put the buildings in good repair. He was a live-stock farmer from the West who just knew from his own experience and from that of the Secretary of Agriculture, in the use of a little clover or farm manure in unlocking the great reserves of an almost virgin soil, that all his Maryland farm needed was clover seed and live stock. Sheep especially he knew to be great producers of fertility.

"He sowed the clover and grass seed and they germinated well. He even secured a fine catch, but it failed to hold, as we say out West. He tried again and again, and failed as often as he tried. He showed me his best clover on a field that had received some manure made from feed part of which was purchased, and that had also received five hundred pounds per acre of hydrated lime, which he was finally persuaded to use, after becoming convinced that clover-growing on old abandoned land was not exactly as easy as clover-growing on a 'run-down' farm of almost virgin soil in the West."

"And was the clover good after that treatment?" asked Mr. West.

"No, not good," said Percy, "but in some places where the manure had been applied to the high points, as is the custom of the Western farmer, the yield of clover, weeds, and foul grass together must have been nearly a half ton to the acre. Fortunately he waited to fully stock his farm with cattle and sheep until he should have some assurance of producing sufficient feed to keep them for a time at least, instead of making the common mistake of the less experienced farmer who goes to the country from the city, and who imagines that, if he has plenty of stock on the farm, they must of necessity produce abundance of manure with which to enrich his land for the production of abundant crops."

"Well, now you'll have to show me," said the grandmother. "To my way of thinking that's a pretty good kind of a notion for a farmer to have, and I'd like to know what's wrong with it."

Again a shadow seemed to cross the sweet face as the mother's glance turned from grandma to Adelaide.

"The system has some merit," replied Percy, "but it starts at the wrong point in the circle. Cattle and sheep must first have feed before they can produce the fertilizer with which to enrich the soil; and people who would raise stock on poor land should always produce a good supply of food before they procure the stock requiring to be fed. There is probably no more direct route to financial disaster than for one to insist upon over-stocking a farm that is essentially worn out."

"But doesn't pasturing enrich the soil?" asked the grandmother.

"Pasturing may enrich the soil only in a single element of plant food," said Percy. "In all other elements simple pasturing must always contribute toward soil depletion. If the pasture herbage contains a sufficient proportion of legume plants so that the fixation of free nitrogen exceeds the utilization of nitrogen in animal growth, then the soil will be enriched in that element, although with the same growth of plants it would be enriched more rapidly without pasturing; for animals are not made out of nothing. Meat, milk, and wool are all highly nitrogenous products.

"On the other hand no amount of pasturing can add to the soil a single pound of any one of the six mineral elements, and phosphorus, which is normally the most limited of all these elements, is abstracted from the soil and retained by the animals in very considerable amounts. As an average one-fourth of the phosphorus contained in the food consumed is retained in the animal products, especially in bone, flesh, and milk."

"Well, I didn't know that milk contained phosphorus," said Mr. West, "although I did know, of course, that phosphorus must be contained in bone."

"But, as you know," said Percy, "milk is the only food of young animals, and they must secure their bone food from the milk. Furthermore, the complete analysis of milk shows that it contains very considerable quantities. There are also records of digestion experiments in which less than one-half of the phosphorus in the food consumed was recovered in the total manural excrements. As a matter of fact there is a time in the life of the young mother, as with the two-year old cow, for example, when she must abstract from the food she consumes sufficient phosphorus for the nourishment of three growing animals,—her own immature body, a suckling calf, and another calf as yet unborn.

"Of course the organic matter of the soil should increase under pasturing, especially under conditions that make possible an accumulation of nitrogen; but here too the animals make no contribution toward any such accumulation. With the same growth of plants the accumulation of organic matter would be much more rapid without live stock."

"It is known absolutely but not generally that live stock destroy about two-thirds of the organic matter contained in the food they consume. With grains the proportion is higher, and with coarse forage it is lower, but as an average about two-thirds of the dry matter in tender young grass or clover or in a mixed, well-balanced ration of grain and hay is digested and thus practically destroyed so far as the production of organic matter is concerned.

"This you could easily verify yourself, Mr. West, by feeding two thousand pounds of any suitable ration, such as corn and clover hay, collecting and drying the total excrement, which will be found to weigh about seven hundred pounds, if it contains no higher percentage of moisture than was contained in the two thousand pounds of food consumed.

"Of course one should not forget that the liquid excrement contains more nitrogen and more potassium than the solid, and that much of this can be saved and returned to the land by use of plenty of absorbent bedding, and in pasturing there is no danger of any loss from this source."

"That is one great trouble with us," said Mr. West. "We never have as much bedding as we could use to advantage, and it is altogether too expensive to permit us to think of buying straw."

"Probably it would be much less expensive for you to buy ground limestone and then use good alfalfa hay for bedding," said Percy. "I mean exactly what I say," he continued. "Of course I do not advise you to use good alfalfa hay in that way, but it would be a cheap source of very valuable bedding, and it would make an extremely valuable manure. However, I should not hesitate to make liberal use of partially spoiled alfalfa hay for bedding, and you are quite likely to have more or less such hay; for under favorable conditions, such as you can easily have with your soil and climate, alfalfa comes on with a rush in the spring, and often the first crop should be cut before the weather is suitable for making hay. There should be very little or no delay at this time, because the first cutting should be removed in order that it may be out of the way of the second crop, which comes forward still more rapidly under normal conditions.

"Some of our Illinois farmers make strenuous objection to taking care of an alfalfa field that produces $50 worth of the richest and most valuable hay, because it interferes too much with the proper care of a $25 corn crop, which they somehow feel requires and deserves all their time and attention.

"Some of our Virginia farmers have sent to Illinois for their seed corn," said Mr. West; "and they report very good results as a rule, especially on land that has been kept up. On our poor land I think the native corn does better than the Western seed."

"Perhaps that is because it is used to it," suggested Percy, "used to making the struggle for itself on poor land. Fighting for all it gets, so to speak. You know the high-bred animals cannot hold their own with the scrubs when it comes to pawing the snow off the dead wild grass for a living in the winter, as cattle must do sometimes on the plains of the Northwest.

"Well, there may be something in that," responded Mr. West, "but the western seed corn certainly looks fine."

"Yes, that is true," said Percy. "Our farmers have made marked improvement in seed corn; they also understand very well how to grow corn. They know how and when to prepare the ground, how and when to plant; and how and when to cultivate. When Illinois farmers go to Iowa to buy land, the Iowa real estate men usually take them to see a farm that is owned and operated by a former Illinoisan, and they insist that there are no other farmers who know how to raise corn quite so well as the Illinois farmer. Perhaps the Illinois real estate man would tell a similar story to the Iowa farmer if he ever came there to buy land, but 'Westward the Course of Empire takes its Way' and the man once gone west knows the east no more, except as a market for his surplus products or a good place in which to spend his surplus cash.

"But, here. We must finish our study of the data that Miss Adelaide so kindly helped me to compute."

It was the first time that he had spoken her name in her presence; and she met his glance as she raised her eyes.

What's in a name? What's in a glance?

Percy proceeded without delay; and Adelaide listened as before, her drooping lashes protecting her eyes almost entirely from the view of others. The father and mother heard no name spoken and saw no eyes meet, and yet as Percy continued speaking a second self seemed to be thinking different thoughts and he was conscious of a strong desire to look longer than an instant into those captivating eyes.

A side glance, as she let her lashes droop, revealed to Adelaide that grandma alone had heard and seen. But Percy was a very common-place man. Certainly he had no such face as had held her glance for more than an instant as the afternoon train began to move from the depot platform. Percy was slightly above the average height and solidly built, but he was not tall. His face had often been described as a "perfect blank." No one saw anything of what lay within by merely looking into his eyes, and yet there was a certain indescribable something that appealed to one from those eyes. An elderly German lady once remarked to his mother: "Ihr Sohn hat so etwas gutes im Auge."

Percy was not polished in manner, Adelaide admitted. Professor Barstow had said that he deliberated for half an hour as to whether he should bring his "cawds," for use on Thanksgiving day, because he feared that the custom in "Vi'ginia" might not be the same as in "No'th Cahlina"; while she doubted very much if Percy had any cards whatever. She had never heard it said that he was "strong as an ox and quick as lightning," but perhaps she knew it as well as his schoolmates ever had. She had not heard that one of the college professors, noted for his short-cut expressions, had once told his class that he wished they would all "keep their thinking apparatus in as good repair as Johnston's." One thing she did know was that Percy's voice had been trained to talk to a woman, and that no other voice had ever spoken her name as he did. Reserve force? depth of manhood? confidence in his own words? absolute decision? wealth of tenderness? persistent endurance? unfailing loyalty? boundless affection? Deep in her heart Adelaide felt that these were among the attributes revealed in Percy's voice. When he spoke all listened. His voice was low-pitched but rich in tone and volume and sincerity,—that was the word.—The whole man seemed to feel and speak when he spoke. He surely can have no secrets. His mother must know all that he knows of his own self; but were those letters from his mother? The handwriting was very modern. Even her father made an old-fashioned C and W in signing his own name. Had he not looked at the writing on both those letters before he noticed the others? and why did he remain so long in his room before coming down to dinner? Had he not been in college—in a great University where there were hundreds of the brightest girls of his own State? But why should any girl be interested in farming? Teaching is such a cultured profession.

Only a moment—just while he was sorting the papers upon which they had made the computations, but a hundred thoughts had passed through her mind. Now he was speaking.

"You remember we took a sample of the subsoil on the sloping land. This soil is evidently residual, formed in place from the disintegration of the underlying rock. The soil may represent only a small part of the original rock, because of the loss by leaching. Here are the amounts of plant food found in two million pounds of the subsoil:

590 pounds of nitrogen 1,980 pounds of phosphorus 37,940 pounds of potassium 24,808 pounds of magnesium 31,320 pounds of calcium

"A splendid subsoil," Percy continued. "I know of none better in Illinois, except that we sometimes have more calcium in the form of carbonate, and even somewhat more potassium in places; but this must be a fine subsoil for alfalfa, where the bed rock is not too near the surface. Of course there is but little nitrogen in the subsoil, but that is true of all normal soils, because the nitrogen is contained only in the organic matter, and that decreases rapidly with depth and usually becomes insufficient to color the soil below 18 inches."

"Now," began Mr. West, "from these different analyses or invoices, and from your discussion of these results, I take it that you would not advise me to purchase any commercial fertilizer for use on the land we are still using in my rotation; but you think we should make large use of limestone and legume crops."

"Yes, Sir. Phosphorus is markedly deficient only in the very level upland which has been allowed to remain uncleared for fifty years or more, and nitrogen is certainly the limiting element on the land you are trying to keep in your rotation. While you cannot hope to put into your soil any such reserve of slow-acting organic matter as we still have in our comparatively new soils of the West, we may keep in mind that a small amount of quick-acting fresh organic matter is more effective than a large supply of what we might call embalmed material that decomposes very, very slowly unless assisted by the addition of more active organic matter. It frequently happens that one soil containing a large reserve of old humus, and hence showing more organic carbon and more nitrogen, by the ultimate invoice, than another soil, is, nevertheless, less productive, because the other soil contains a larger amount of fresh organic matter which decays quickly and thus furnishes more nitrogen and liberates more of the other elements from the insoluble minerals of the soil because of the greater abundance of the active products of organic decay.

"I think you should keep in mind, however, that, for every twenty-five bushels of corn you wish to produce, you should return to the soil one ton of clover or four tons of average farm manure, and that for one ton of produce hauled to the barns and fed, you will probably not return to the land more than one ton of manure."